Supplemental signaling system for special railway vehicles



March 3, 1953 w. v. GROSJEAN 2,630,524

SUPPLEMENTAL SIGNALING SYSTEM FOR SPECIAL RAILWAY VEHICLES 3 Sheets-Sheet 1 Filed Jan. 7. 1948 NV T I. F T u A ENE W H i 7 n n b Vfir'oksjean BY 2 H15 ATTORNEY d m INVENTOR.

3 Sheets-Sheet 2 mu 8& G

W. V. GROSJEAN SUPPLEMENTAL SIGNALING SYSTEM FOR SPECIAL RAILWAY VEHICLES March 3, 1953 V Filed Jan. 7. 1948 March 3, 1953 w. v. GROSJEAN 2,630,524

SUPPLEMENTAL SIGNALING SYSTEM FOR SPECIAL RAILWAY VEHICLES Filed Jan. 7, 1948 3 Sheets-Sheet 3 5 a w k N N N Q a N -1 IN V EN TOR.

54 Wilb V Gmsjean H115 ATTORNEY Patented Mar. 3, 1953 UNITED STATES PATENT OFFICE 2,630,524 SUPPLEMENTAL SIGNALING SYSTEM Fo'E sPEcIAL RAILWAY VEHICLES Wilbur V. Grbsjean, Omaha, Nehru "ass'ignor to Westinghouse Air Brake compan a corpor'ation 55f Penns lvania Application Januar 7, 1948, serial No. 9'96 (01. Meme-*1) claims. 1

My invention relates to railway 'signaling sys= terms, and particularly to a supplemental railway signaling system for governing the movement of special rail-way vehicle's over tracks equipped with a block signaling system which such vehicles are incapable of controlling.

Special railway vehicles, such as small motor cars used by maintenance forces, are usually equipped with insulated Wheels or axles so that these cars will not shunt the track circuits of signaling systems which govern train movements in the stretch over which the cars operate. As a result, the conventional railway signaling systems do not protect the operator of a motor car or other special vehicles of that character.

The principal object of my invention is to provide a supplementary signaling system for governing indicators on special railway vehicles, whereby the operator of such a vehicle is warned of the approach of a train in ample time to remove the vehicle from the rails.

Another object of my invention is to provide an iiiaproved signalling system for railway motor cars or the like which operates Without interfering with the normal operation of railway signaling systems provided for the protection of train movements. l e

A rurtherobj'ect or invention is t provide an improved system of the type described eiiilaying a minimum "or auxil apparatus in conjunction with the usual s gnali'n'g' equipment.

Another object of my invention is to provide an improved system of the type described which may be employed in conjunction with a "conventio'n'al absolute permissive block signaling "system.

"Other objects or invention and features of novelty will be apparent from the following description taken in connection with the accomartying drawings.

In practicin invention, I provide moication means on each special 'veh'i'cl'e whi'clijs adapted to respond selectively to current in the track rails of such oh'aract'e'r that it is readily distinguishable from the current normally supplied for the control of the track relays, and the vehicle is also rendered incapable of shunting the track relays by insulating the wheel's. I then provide a system of wayside control circuits governed by the track relays, and so rendered responsive to the presence or approach of a train, for supplying current of the character to which the indication means is responsive to each "track section of the protected 'sti'e'tch of track.

This current for the control of the 'rn'otor car indicators is supplied to the rails or a section only when the track relay for the section is ener ized and traffic conditions, as reflected by the track relays "for adjoining sections, are such as to indicate that there is no train approaching within 'a predetermined distance of such t'rack s'ection. y

In the specific embodiment or my invention disclosed herein, the railway signaling "system provided for the protection of train movements is "a -coiulentional absolute permissive block signaling system for "a single track railroad, employin'g the usual direct current track circuits for the detection of the presence of trains, and the current supplied to the track rails for the protection of the "special vehicles is alternating current superimposed upon the direct current suppiied "to the rails for the control of the track relays. The circuits for supplying the a1ternati'ng current to a block section are governed by the signal control relays of the "absolute permissive block signaling system which relays are controlled over line "circuits by the track relays, so that steady alternating current energy is normally supplied to each track circuit in the block section. When a train enters the block, the shunting Of the track relay for the first Section of the block causes the signal control relays to release, thereby interrupting the supply of alternating "current energy to the various track circuits included in the seot'ion. As the train progresses through the block, the directional stick relays provided in the signaling system become picked -up, to thereby supply alternating current energy to the track circuits in the rear of a train. in addition, at certain locations means are provided by which the supply of alternating current is coded or periodically interrupted when a train approaches within a certain distance, to thereby provide adist inctive indication on a motor car or other special vehicle equipped with apparatus for detecting the presence or absence of alternating current in the track rails.

I shall describe two forms of apparatus embodying my invention and Shall then point out the novel features thereof in claims.

Referring to the accompanying drawings, Figs. 1A and 1B, taken together constitute a diagrammatic view of a stretch of railway'track equipped with 'a conventional four line Wire absolute permissiv'e block signaling system and also with asupplemental signaling system incorporating my invention,

Fig. 2 is a diagrammatic view of a modification of the equipment shown in Fig. 1A which I may employ, and

3 is a diagrammatic view of a preferred form of indication equipment which may be applied to a railway motor car to be used in cooperation with the wayside apparatus of my invention. Figs. 1A and 13 when placed side by side with Fig. 1B at the right of Fig. 1A illustrate the circuits and apparatus embodying my invention as applied to a stretch of single track between two passing sidings PS, and when Fig. 1B is placed at the left of Fig. 1A these views illustrate the circuits and apparatus embodying my invention as applied to the main track stretch adjoining a passing siding interposed between two single track stretches.

In most instances in the drawings the relay contacts are located directly in line with the Winding of the relay, but in some cases in order to simplify the drawings, relay contacts are separated from the relay winding and in these instances the relay with which the contacts are associated is designated by appropriate reference characters placed above the contacts.

The main track, as shown, is equipped with automatic block signals IS to 88, inclusive, and is divided into track sections IT to 8T, inclusive, each equipped with the usual normally closed track circuit having a track relay TR at one end energized by a track battery TB connected across the rails at the other end. In addition, at the relay end of each track section the secondary winding of a track transformer TT is connected across the rails in series with a limiting impedance R. When alternating current is supplied to the primary winding of the track transformer, alternating current is induced in the secondary winding and is supplied to the rails of the section. The windings of the track relays present a high impedance to the alternating current, and a reactor is connected in series with each of the track batteries TB as shown so that the flow of alternating current through the windings of the track relays is negligible, and that which flows through the track batteries is alsoreduced. Accordingly, it will be seen that the alternating current energy may be supplied to a track circuit section without aifecting the operation of the direct current track circuit.

As shown, the signals are of the well-known color light type, governed by polarized signal control relays I-IDR which are of the retained neutral type. The HDR relays are controlled over cascade-connected line circuits which include front contacts of the track relays. The polarity of the energy supplied to each I-IDR. relay is governed in accordance with the position of the similar relay for the next signal in advance or by a pole changer relay PCR controlled th-ereby, and at intermediate locations by directional stick relays SR such as are generally provided in systems of this character.

A local source of energy is provided at each location to energize the relays other than the track relays, which source is not shown, but whose positive and negative terminals are designated B and C, respectively. In addition, a source of alternating current, not shown, is provided at each signal location, the terminals of which are designated as BX and CX.

Each signal is provided with three lamps, as shown in detail for head block signal is, including a red lamp R which is lighted to indicate stop when the controlling relay HDR is deenergized, a yellow lamp Y which is lighted to indicate caution when the relay HDR is energized by energy of reverse polarity, and a green lamp G which is lighted to indicate proceed when the relay HDR is energized by energy of normal polarity. The lamps of each intermediate signal, such as signal 35, are supplied with energy over lighting circuits similar to that for signal IS, except that the red lamp R is provided with an additional circuit which includes a front contact of the opposing directional stick relay, and

the circuits for supplying energy to the lamps Y and G in addition to being controlled by the conleased position to which it moves when the sup-v ply of energy to the relay winding is cut off. Each flasher relay such as relay I ZR operates periodically when energy is supplied to its winding, and its contact a recurrently picks up and releases at a relatively slow rate, such as 35 cycles per minute, for purposes hereinafter explained. Each flasher relay is identified conventionally on the drawings by a circle on the representation of its winding.

Referring now to Figs. 1A and 1B placed side by side with Fig. 13 at the right, the equipment for the single track stretch between the passing siding PS as shown is in its normal condition with no train in the vicinity. As previously stated, the signaling system is of the conventional four line wire absolute permissive type. Under normal conditions with no train in the vicinity each of the signal control relays BBB is energized by energy of normal polarity and as a result, each signal displays a proceed aspect.

At this time, at the head block signal location lS--2S steady alternating current energy is supplied to the primary winding of transformer ITT over a circuit which is traced from terminal BX at front contact a of relay ZHDR, over front contact c of relay lI-IDR, and through the primary winding of transformer ITT to terminal CX. As

a result, alternating current is induced in the secondary winding of track transformer ITT and is supplied to the rails of section IT. Alternating current is also supplied to the primary winding of track transformer 2TT over the circuit which is traced from terminal BX at front contact a of relay ZHDR, over back contact a of relay IZR, normal polar contact I) of relay IHDR, and front neutral contact 01 of relay IHDR and through the primary winding of transformer ZTT to terminal GK, and as a result, steady alter-' SHDR, and through the winding of transformer 3TT to terminal CX. Also steady alternating current is supplied to the primary winding of track transformer 4TT over the circuit from terminal BX, over front contact a of relay 3HDR, over front contact b of relay 4HDR, and through the primary winding of transformer 4T1 to terminal OX. Accordingly, at this time steadyah ternating current energy is supplied to the rails of sections 3T and 4T.

It will be apparent from the drawings that the signal control circuits are symmetricaland at head block location 'lS8S steady alternating current is supplied to the rails of sections IT and ET by circuits similar to those previously ue= scribed for head block location lS- QS. Also, steady alternating current is supplied to the rails of sections ET and EST at intermediate signal location 55-63 by circuits similar to those described for location 3S--4S.

From the foregoing it will be seen that with the apparatus in its normal condition and with no train in the vicinity. steady alternating current is supplied to the rails of each of the track circuit sections of the main track portion of the track stretch. H

Referring now to Fig. 3, there is shown a dia-= grammatic view of one arrangement of indication apparatus which may be employed on motor or other special cars which are operated over the stretch of track described above. As shown, the wheels WI and W2 are insulated from each other by the insulated joint IJ in the axle AX, and the other pair of wheels, not shown, on the motor car are similarly insulated, so that the car will not shunt the track circuit. A slip ring SR1 makes electrical contact with the wheel WI and a second slip ring SR2 makes electrical contact with the wheel W2. Connected in series between the slip rings SR! and SR2 are the condenser IQ and the primary winding of a transformer IT. The secondary winding of the transformer IT is connected to the input terminals of a bridgetype rectifier IRX, and the winding of an indicator relay IR is connected across the output terminals of this rectifier. It will be apparent that when the car moves over the rails of a track section the condenser IQ will prevent the flow of direct current track circuit energy, but will permit the flow of alternating current through the primary winding of the transformer IT. The alternating current induced in the secondary winding of transformer IT is rectified by rectifier IRX, and is supplied to the winding of relay IR, and as a result, relay IR picks up to establish a circuit, obvious from the drawing, for supplying energy over its front contact from the battery IE to light the indicator lamp KE. If the supply of alternating current to the rails R is interrupted, energy will no longer be supplied to the winding of relay IR and its contacts will release, extinguishing the lamp KE, and establishing a circuit for supplying energy to a warning bell KS. A switch SW is shown in series with the circuit for supplying energy to the indication lamp KE and the warning bell KS, so that the equipment may be deenergized when the car is removed from the rails. I

It is to be understood that my invention is not limited to the specific arrangement of vehiclecarried indicator equipment shown in Fig. 3, and any suitable means for detecting a characteristic of the current supplied to the track rails which differs from that depended upon for the energization of the track relays may be employed. When alternating current is employed, as shown herein, the relay IR may be inductively coupled to the track rails by the provision of receiving coils on the motor car in inductive relation to the rails, together with an amplifier for amplifying the energy induced in such coils, such an arrangement being well-known from its use for the control of train carried cab signals.

It willb'e seen that if a car equipped with ap paratu's as shown in Fig. 3 travels over the stretch or track shown in Figs. 1A and 1B at a time when the system is in its normal condition with all of the track relays picked up, each of the track 'sec-' tions will supply alternating current to the apparatus on the "car in turn and the relay IR on the car will remain energized, thus causing the lamp KE to remain lighted, and thereby indicate to the operator of the motor car that he may safely continue running.

It will be readily apparent, however, that the system of my invention differs very materially from the conventional cab signaling systems for the continuous control of train movements by apparatus responsive to alternating current in the track rails. In such systems, the track re lay for the occupied section is shunted by the wheels and axles of the train, which complete a path for the cab signaling current in the rails in front "of the train and this current is supplied to the rails at one end of the section or the other depending upon the traflic direction established. The motor car indicator current, on the other hand, is supplied at one end only of each section, for either direction of motor car operation, and then only in the absence of a train shunt. That is to say, the motor car current is supplied to the rails of a section over a circuit governed by the front contacts of the track relay for the section at a time when cab signaling current is not needed. It follows that a cab signaling system which embodies the appreach control principle in which the control current is supplied to the rails of a section in response to the release of the track relay may be used in "conjunction with my motor car indicator system without interference, merely by a choice of currents of different character for the two systems.

Placing Fig. 1B at the right of Fig. 1A, it will he assumed that an eastbound train, that is to say, a train moving from left to right in section IT enters section'2T of the single track stretch. Relay ITR is released, consequently II-IDR is released and its contacts 0 and d in the circuits for transformers ITT and 2TT open, cutting off the supply of alternating current from the rails or sections IT and 2T.

When the train enters section 2T, relay ZT-R releases, releasing relay 2HDR to restore signal 2S to stop and also releasing the cascade-connected relays 3I-IDR, EHDR and THDR to restore the opposing signals 38, 5S and IS in accordance with the usual operation of an absolute permissive block system, and to open the circuits for the transformers STT to 8TT, inclusive, cutting off the supply of alternating current from the rails of sections 3T to BT.

Placing Fig. 1A now at theright of Fig. IE to enable conditions in the single track stretch at the right of the one occupied by the approaching eastbound train to be more readily visualized, it will be seen that the release of relay 'IHDR as above described reverse-s the polarity of the current suppliedto relay lHDR, so that signal IS at the right displays yellow aspect. When polar contact a of relay IHDR moves to its reverse position it opens the circuit for the pole changer relay IPCR, which releases and thereby reverses the polarity of the current supplied to relay 3I-IDR so that signal 3S also dis plays a yellow aspect at this time. When polar contact (2 of relay IHDR closes in its reverse position a circuit including front neutral con- 7 tact a of relay IHDR is established for supplying energy to the flasher relay IZR. When polar contact b of relay IHDR moves to its reverse position, it interrupts the previously traced circuit including back contact a of flasher relay I ZR for supplying steady alternating current to the transformer ZTT. At this time, alternating current is supplied steadily to transformer ITT,

by a circuit which may be traced from terminal BX at front contact a of relay ZHDR, over front contact of relay IHDR, and through the primary winding of transformer ITT to terminal CX. Additionally, alternating current energy is supplied to the primary winding of transformer ZTT only during the picked up periods of contact a of relay IZR over the circuit from terminal BX at front contact a of relay ZHDR, over front contact a of relay IZR, and front contact d of relay IHDR through the winding of transformer 2TT to terminal CX. As a result of the recurrent operation of contact a of relay IZR, the alternating current supplied to the primary Winding of transformer ZTT is coded or recurrently interrupted, so that spaced impulses of alternating current are applied to the rails of section 2T at this time.

Also, when the polar contacts of relay 3'HDR move to their reverse position, contact d establishes an obvious circuit for supplying energy to the winding of relay 3ZR, while contact b of relay SHDR interrupts the circuit for supplying steady alternating current to transformer 3TT. At this time, alternating current energy is supplied to the primary winding of transformer 3TT during the picked up periods of contact a of relay 32R over the circuit from terminal BX at front contact a of relay AHDR, over front contact a of relay 32R, and front contact 0 of relay 3HDR through the primary winding of transformer 3TT to terminal CX. As a result of the recurrent operation of contact a of relay 3ZR, the alternating current supplied to the track section 3T is periodically interrupted.

It will be apparent, therefore, that at this time the alternating current supplied to the track sections 2T and 3T is coded or recurrently interrupted so that if a motor car equipped with the indication apparatus shown in Fig. 3 is occupying section 2T or 3T, the indication lamp on the car will be recurrently flashed and the Warning bell recurrently sounded to warn the operator of the approach of an eastbound train in the single track stretch beyond the passing siding PS at his left. At this time steady alternating current continues to be supplied to sections 4T to BT, inclusive, at the right of the section 21 or 3T occupied by the motor car, and also to section IT adjoining these sections at the left.

From the foregoing it will be seen that if a motor car is proceeding westwardly through the single track stretch at a time when an eastbound train is approaching the passing siding at the left, the indicator on the motor car will provide a steadily lighted indication on the lamp KE, until the motor car passes signal 38 and enters section 3T. When the motor car enters section 3T, and as the car proceeds through sections 3'1 and 2T, the reception of the periodically interrupted alternating current energy will cause the relay IE on the motor car to be periodically picked up and released, with the result that the indication lamp KE is flashed and the bell KS is periodically sounded. This distinctive operation f the warning equipment will indicate to the motor car operator that a train is approaching the passing siding from the opposite direction, but is not yet dangerously near. In such a case, the motor car operator can then speed up his car sufliciently to arrive at the passing siding in sufflcient time to move the car into the passing siding, rather than to remove the car from the rails immediately.

When the approaching eastbound train advances into section lT' at the west end of the siding PS, the supply of current to relay IHDR i cut off and its neutral contacts release, thereby causing the signal is to indicate stop. When neutral contacts c and d of relay lHDR, release, they interrupt the circuits traced above for supplying alternating current to the transformers HT and ZTT, and as a result, the supply of alternating current energy to the rail of section IT and 2T iscut off. Relay 3I-IDR remains energized with energy of reverse polarity at this time, so that the supply of recurrently interrupted alternating current energy to section 3T continues.

Accordingly, when a train approaching the siding PS from the left occupies section 1T, the indication lamp on a motor car approaching this siding from the right will be continuously lighted until the car enters section 3T, whereupon the light will be recurrently flashed and the bell will recurrently sound to caution the operator that a train has occupied a section in advance. When the motor car advances into section 2T or section IT, no alternating current energy will be received from the track rails and the lamp on the car will remain dark and the bell will operate continuously to thereby warn the operator that a train is dangerously near.

Assuming now that the motor car remains in one of the sections 3T8T of the single track stretch until the approaching eastbound train passes the entering signal 28 for that stretch, the release of the track relay 2TB, will release the relays HDR and thereby deenergize the transformers T1" for sections 3T to 8'1, inclusive, as already described for the similar ingle track stretch at the left of the one now under consideration. It follows that the indication means on a motor car present anywhere in this single track stretch will no longer receive alternating current, and the lamp of the indication means Will become dark and the warning bell will sound, thereby warning the operator of the approach of a train.

Considering now conditions in the rear of the eastbound train which is moving through the single track stretch, it will be seen that when this train enters section 3T, the track relay 3TB releases, and its contacts additionally interrupt the circuits for relays ZHDR and SHDR, so that these relays remain released. In addition, upon the release of relay 3TB, a pick-up circuit for the eastbound directional stick relay 45R i established from terminal B, at back contact a of the westbound directional stick relay SSR, over back contact a of relay 3TB, front neutral contact 0 of relay 4I-IDR, and through the winding of relay 48R to terminal C. When relay 48R picks up, its front contact a establishes a stick circuit therefor extending from terminal B at back contact a of relay SSR, over back contact a of relay 3TH, over front contact a of relay a-SR, and through the winding of relay 4BR to terminal C. When relay 48R picks up, its contact I) interrupts the circuit for supplying energy to the 9 lamps Y and G of ignal 38, and establishes a circuit for supplying energy to the red lamp R of the signal, which circuit, as previously explained is independent of the circuit controlled by the signal control relay 3HDR for supplying energy to this lamp.

When the eastbound train vacates section IT, the track relay I TR picks up and relay IHDR, becomes energized by current of normal polarity. However, as explained above, when relay IHDR picks up the supply of current to the transformers ITT and ZTT continues to be interrupted by front contact a of relay 2HDR which relay remains released until the train vacates section 3T.

When the train enters section 4T, relay 4TB releases, and interrupts the circuit of relay AHDR and when relay 4HDR releases, an additional stick circuit is established for relay lSR extending from terminal B, at back contact a of relay 3SR, over back contact of relay ll-113R, front contact a of relay 48R, and through the winding of relay 4BR to terminal C;

When the rear of the train vacates section 2T, relay ZTR picks up, but relay ZHDR remains released to cut off the supply of alternating current from section IT and 2T, since its circuit is interruptedby a contact of track relay STR.

When the train enters section 5T, relay 5TB releases, opening it contacts in the circuits of relays EHDR and dHDR, so that these relays remain released after section 4T is vacated. In addition, when relay 5TB releases, its contact a establishes the pick up circuit for the directional stick relay GSR, which extend from terminal B at back contact a of relay SSR, over back contact a of relay 5TB, front contact a of relay Gl-IDR, and through the winding of relay 68R to terminal C; When relay BSR picks up, it establishes a stick circuit which extends from terminal B at back contact a of relay 53R, back contact a of relay 5TB, and itsfront contact a and winding of relay BSR to terminal C. When relay GSR picks up it establishes a circuit for supplying energy to the red lamp R of signal 5S by a lighting circuit not shown but similar to that hown for signal as, so that the red lamp R,- of signal 58 is lighted independently of the circuit controlled by relay EHDR.

When the train vacates section 3T, track. relay 3TB; picks up, and its contacts complete the circuits for relays ZHDR and 3HDR. Relay Zl-IDR is now energized by current of reverse polarity over connections controlled by back contacts of relay lHDR and by front'contacts of relay 48R,

which is picked up at this time. A a result, the signal 23 now displays a yellow aspect. Relay 3HDR. is' now energized by current of normal polarity, but front contact b of relay 48R continues to maintain the circuit for the red lamp R of signal 38 and to interrupt the circuit for the lamps Y'or G of signal 3S as previously explained, so that signal 3S continues to display a 3TT, which extends from terminal BX at front contact 0 of relay 453R, over contacts I) and c of relay SHDR, and through the primary winding of transformer 3TT to terminal CX. It follows that steady alternating current is supplied to the rails of sections IT, 2T and ET as soon as the eastbound train vacate section 3'1, and a motor car moving through these sections will have its indication lamp lighted, thereby permitting a motor car tofollow the train which is moving through the single track stretch from left to right.

When the eastbound train enters section 6T, track relay GTR releases and interrupts the circuit for relay BHDR which releases to cause the signal 63 to display its red aspect. Wh n relay GI-IDR releases, a stick circuit is established for relay BSR, from terminal B at back contact a of relay 58R, over back contact a of relay BHDR, front contact a and Winding of relay 65R. to terminal C. When relay 6HDR releases, it additionally interrupts the circuits for supplying energy to the primary windings of transformers 5T1 and ETT.

When the train vacates section 4T, track relay ITR picks up, but relays 4HDR and EHDR remain released, since the rear of the train still occupies section ET and track relay 5TB, interrupts the circuits of relays 4HDR and EHDR. As relay 4HDR is released, alternating current energy is not supplied to the primary winding of transformer 4TT, so that alternating current energy is not supplied to the rails of section 4T at this time.

When the eastbound train vacates section 51, track relay 5TB again picks up and completes the circuits for relays 4HDR. and EHDR. Relay 4HDR is now energized by current of reverse polarity over a circuit including front contacts of relay SSH. and back contacts of relay BHDR so that when relay 4HDR picks up, the. signal 48 will display a yellow aspect. Relay EHDR is now energized by current of normal polarity and its polar contacts operate to their normal position. However, signal 5S continues to display a red aspect at this time since the stick relay GSR is picked up to light the red lamp of si hal- 58 and interrupt the supply of current to the yellow and green lamps of signal 5s. After relay ll-IDR. picks up, relay 2HDR is supplied with current of normal polarity over the circuit including front contacts of relay 4HDR and back contacts of relay 38R, so that relay Zl-IDR causes signal 28 to display a green aspect.

In addition, when relay 4I-IDR picks up, its contact 0 interrupts the stick circuit for relay 48R and it releases to interrupt the supply of current to the red lamp of signal 3S and to estab lish. the circuit for supplying current over the contacts of relay 3HDR to the yellow and green lamps of signal 35. Since at this time relay 3HDR is energized by current of normal polarity, the signal 3S will display a green aspect. Steady alternating current is supplied to sections 3T and 4T at this time by the circuits previously bound train in section GT or !T will have its accuses 11 indicator lamp lighted, but a motor car entering section 6T at this time will have its indicator lamp extinguished and the bell sounded to indicate the proximity of a train.

When the eastbound train enters section IT, relay ITR, releases and interrupts the circuit for relay IHDR for the opposing signal IS at the right-hand end of the siding in advance of the train, and when the train enters section 8T, relay 8TB. releases and opens the circuit for relay 8HDR, which releases and in turn, opens the circuit for relay BPCR which releases.

When the train vacates section IT, relay ITR picks up and completes the circuits for relays GHDR and 'IHDR. At this time, since relay BPCR is released, the relay BHDR is supplied with current of reverse polarity. When relay BHDR picks up, its front contact a interrupts the stick circuit for the directional stick relay SSH. and it releases. At this time, since relay BHDR. is energized by current of reverse polarity, signal 68 will display a yellow aspect, and since relay SHDR is energized by current of normal polarity, signal 58 will display a green aspect when relay BSR releases. After relay GSR releases, the primary winding of transformer TT is supplied with steady alternating current over the circuit including front contacts of relays 5HDR and BHDR. The primary winding of transformer BTT is supplied with periodically interrupted alternating current energy, since the reverse polar contacts of relay GHDR are now closed to complete a circuit for the flasher relay 62R, and to cause the contact of the flasher relay EZR to be included in the circuit for transformer BTT. Accordingly, a motor car entering section ET in the rear of the train in section 8T will have its indication lamp continuously lighted. but when the motor car moves into section ET, the indication lamp will b flashed in response to the coded alternating current ener y supplied to the rails of the section at this time.

Although IHDR, is now picked up, the contacts of relay BHDR continue to interrupt the supply of energy to the transformers ITT and 8TT so that a motor car entering section IT or 8T at this time will have its indication lamo extinguished and its warning bell will sound continuously to indicate the proximity of a train.

When the train vacates section 2T of the ingle track stretch at the right, relay 8HDR is energized by current of reverse polarity, and steady alternating current is supplied to the rails of section 8T by the closing of the circuit for transformer ITT including front contacts of the relays IHDR. and BHDR, and relay 8ZR. becomes energized and coded alternating current is supplied to the rails of section IT by th closing of the circuit for transformer BTT which includes the contact of flasher relay 8ZR.

When the eastbound train vacates section 3T at the right, relay SHDR is energized by current of normal polarity, so that its contacts are operated to their normal position. At this time steady alternating current is supplied to the primary windings of transformers ITT and 8T1 by the circuits including neutral contacts of relays IHDR and SHDR, and th normal polar contact of relay BI-IDR. while the supply of current to relay BZR is out 01f. At this time relay 8PCR becomes energized, so that current of normal polarity is supplied to the winding of relay GHDR with the result that relay SHDR causes signal (is to display a green aspect. In addition, relay GHDR reestablishes the circuit for sup- 12 plying steady alternating current in place of coded current to section 6T. Relays ZHDR an 3HDR become energized at this time, to supply steady alternating current to sections I'I, 2T and 3T as already described. Accordingly, when the eastbound train vacates section 3T the indication lamp on a motor car operatin in any of the sections 6T, IT, 8T, IT, 2T and 31' in the rear of the train will be continuously lighted.

To summarize, from the foregoing detailed description it will be seen that when an eastbound train passes signal 28, the supply of alternating current is cut oil from sections 2T8T in advance of the train by the release of the signal control relays 3I-IDR, SHDR and IHDR which govern Westbound trafiic movements. In addition, the release of relay IHDR reverses the polarity of the current supplied to the signal control relays IHDR and 3HDR governing the two westbound signals IS and 35 further to the right and these relays change the alternating current supplied to the track sections 2T and 3T in the single track stretch beyond the siding PS which the eastbound train is approaching from steady alternating current to coded or periodically interrupted alternating current.

Accordingly, as soon as an eastbound train passes the headblock signal 28 and enters the single track stretch, the indication means on a motor car located anywhere in the single track stretch, or in section 8T of the main track stretch adjacent the siding PS will provide a, danger indication to warn the operator of the car of the approach of the train and inform the operator of the necessity of promptly removing the motor car from the track. At this time, the current supplied to a limited number of track sections farther in advance of the train is changed from steady to coded so that indication means on a motor car in any one of these sections will provide a distinctive indication showing that a train is approaching but is a considerable distance away.

As the train proceeds through the single track stretch alternating current is supplied to the sections behind the train so that the indication means on a motor car in a section behind the train will provide an indication that no train is approaching. As the train proceeds through the single track stretch, there is no change in the condition of energization of the sections in advance of the train until the train enters the last track section IT of the single track stretch.

When the train enters section IT, the signal control relay I HDR for-the opposing signal IS at the remote end of the siding in advance is released, and as a result, the supply of alternating current to the rails of sections IT and 2T in advance of the train is cut off. Accordingly, when.

the eastbound train enters track section IT at the left-hand or west end of the siding PS, the indication provided by the indication means on a motor car in either of these sections will show that the approaching train is relatively near.

When the train occupies section 8T or IT adjoining the passing siding PS, the release of relay BHDR causes the alternating current to be cut oif from sections ET and IT and coded alternating current to be supplied to section 6T, while the release of relay IHDR causes the alternating current to be out oil from sections IT and 2T and coded alternating current to be supplied to section 3T.

It will be apparent that since the circuits are symmetrical, the operation with respect to train 13 movements from, rightto left: is the same as that described above for a train movement, from left to right, anda detailed explanation of the eflect of a westbound train movement: is unnecessary.

Referring to Fig. 2, this view shows a diagrammatic view of a modification of the, left-hand portion of Fig. 1A, in which the supply of alternating current to the rails of sections IT and, 2T is controlled in such a manner as, to insure that when a train is present in, the stretch at theleft of these sections the indication means on a motor car will not provide a less restrictive indication when the caris in section IT than when the car is in section 2T.

With the apparatus Of Fig. 2 in its normal condition, as shown in the drawing, steady alternating current is supplied to the sections IT and 2T from the secondary windings of transformers ITT and ZTT, respectively. The primary windings of transformers I TT and ZTT are connected in multiple, and at this time are supplied with current over a circuit which extends from ter minal BX at front contact, a of relay ZHDR, over back contact a of relay IZR, normal polarcontact b and front contact 0 of relay- IHDR, through the windings of transformers PET and Z'IY'I to terminal CX. Accordingly, atthis time a motor car present in either section IT or 2T will have its indication lamp steadily lighted.

As previously explained, when a train moving from left to right enters the single track stretch at the left of the passing siding PS, relay THDR releases and causes relay IHDR to be energized by current of reverse polarity so that signal IS displays its yellow or caution indication.

When the polar contacts of relay ll-IDR reverse, contact 22 interrupts the previously traced circuit for supplying steady alternating current to transformers I'IT and ZTT While neutral contact c in the circuits of; these transformers remains closed.

When the polar contact a of relay' lI-IDR. reverses, it establishes the, circuit. for supplying energy to the winding of" flasher relay IZR, and

as a result, recurrent pulses of. alternating current are supplied, to the primary windings of transformers ITI and ZTT over the. circuit. from, terminal BX at front contact. a of relay L'HDR, over front contact a of relay IZR, front contact 0 of relay IHDR, through the windings of, transformers ITT and 2TT to terminal CX.

Accordingly, at this time the indicator lamp on a motor car present in either section iT or 2T will flash and the associated bell will recurrently sound to indicate that an eastbound train is appreaching in the single track stretch at, the" left but has not yet entered, section IT. This insures that the indication means on a;westlmundmotor. car will. continue to. display its caution indioartion when the car passes from section 2'1? to IT; When the eastbound train, enters section lTITR, relay IHDR is released as already described in connection with Fig. 1A, andv its neutral front contact c interrupts the supply of alternating For the control by westbound trains, circuits similar to those of Fig; 2 but oppositely directed may be provided. for sections l'I and BT, controlled by relay 8IIDR instead of by relay IHDR, as will readily be understood.

It will be understood by those skilled in the art that: the, arrangement of apparatus embodying my invention is not limited to application to a conventional absolute permissive clock signal,- ing system such as is shown and described herein, but that; it may be applied to any of the various. well-known block signaling systems,

Although I have here-in shown and described only two forms of apparatus embodying my invention, it is to be understood, that. various changes: and modifications herein, may be made within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is;v

1;. A supplemental signaling system for a stretch of; railway track through which special vehicles as well as, trains, are operated at times, said special vehicles being equipped'with insulated wheels and having indication means thereon selectively responsive to current of a distinctive character in the track rails, therailsof said track stretch being divided into a plurality of successive track sec tions each provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, said track stretch being providedwith a principal signaling system comprising a system of circuits governed by said track relays for thecontrol of railway signals governing train movements into and through said stretch in a given direction, said system of circuits being arranged to hold said signals at stop when a train moving in the opposite direction enters said stretch, said supplemental signaling system comprising means for normally supplying; current of said distinctive character to the rails of each of the track sections in said stretch and to which current ofdistinctive character the track relays are nonresponsive, and means governed by said system of circuits for cutting oil" said current of distinctive character from the rails of each of the sections in said stretch when a train enters said stretch.

2. A supplemental signaling system for a stretch of railway track through which special vehicles as well as trains are operated at times, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsive to current of a distinctive character in the track rails, the rails of said track stretch being divided into a plurality of successive track V sections each provided with a track circuit comnaling system comprising a first system of circuits governed by said track relays forthe control of railway signals governing the movement of trains into and' through said stretch in a given direction and a secondsystem of circuits governed by said track relays for the control of railway signals governing movement of'trains-into and through said stretch in the opposite direction, said systems of circuits being arranged so that when a train moving-in either direction enters said stretch the. signals for governing the movement of trains in the other direction are held at stop, said supplemental signaling system comprising means for, normally supplying current of saidselected character to the rails of each of the track sections in thelstretch, and to which current of distinctive 15 character the track relays are non-responsive, and means governed by said systems of circuits for cutting off the supply of said current of distinctive character from the rails of all of the sections in the stretch whenever a train enters said stretch at either end.

3. A supplemental signaling system for a stretch of railway track through which special vehicles as well as trains are operated at times, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsive to current of a distinctive character in the track rails, the rails of said track stretch being divided into a plurality of successive track sections each provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, said track stretch being provided with a principal signaling system comprising a first system of circuits governed by said track relays for the control of railway signals for governing movement of trains into and through said stretch in a given direction, and a second system of circuits governed by said track relays for the control of railway signals governing movement of trains into and through said stretch in the opposite direction, said systems of circuits being arranged so that when a train moving in either direction enters said stretch, the signals governing the movement of trains in the other direction are held at stop, said supplemental signaling system comprising means for normally supplying current of said distinctive character to the rails of each of the sections in the stretch and to which current of distinctive character the track relays are non-responsive, means governed by said systems of circuits for cutting off the supply of said current of distinctive character from the rails of all of the sections in the stretch which are in advance of a train moving through said stretch in either direction, and means governed by said systems of circuits for reestablishing the supply of said current of distinctive character to the rails of the sections in the rear of such train one section at a time as such sections are vacated.

4. A supplemental signaling system for single track railroads having the usual stretches of single track between the ends of adjacent passing sidings through which special vehicles as well as 7 trains are operated at times, said special vehicles being equipped with insulated wheels and havin indication means thereon selectively responsive to current of a distinctive character in the track rails, the rails of said single track stretches and of the main track stretches adjacent the passing sidings being divided into track sections each of which is provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by rains but not by said special vehicles, each of said stretches being provided with a principal signaling system comprising a first and a second system of circuits governed by the track relays of the track sections therein, the first and second system of circuits associated with each stretch controlling signals governing movement of trains into and through the stretch in opposite directions, and arranged so that on entrance of a train into such stretch at either end the signals governing movement of trains in the opposite direction are held at stop, said supplemental signaling system comprising means for normally supplying current of said distinctive character to the rails of each of the sections and to which current of distinctive character the track relays are nonresponsive, and means for each stretch governed by the systems of circuits associated therewith for cutting oii the supply of said current of distinctive character from the rails of all of the sections in said stretch on entrance of a train into said stretch from either end.

5. A supplemental signaling system for single track railroads having the usual stretches of single track between the ends of passing sidings through which at times special vehicles as well as trains are operated, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsive to current of a distinctive character in the track rails, the rails of said single track stretches and of the main track stretches adjacent the passing sidings being divided into track sections each provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, each of said stretches being provided with a principal signaling system comprising a first and a second system of circuits governed by the track relays of the track sections therein, the first and second system of circuits associated with each stretch controlling signals governing movement of trains into and through the stretch in opposite directions, the systems of circuits associated with each stretch being arranged so that on entrance of a train into such stretch at either end the signals governing movement of trains in the oposite direction are held at stop, said supplemental signaling system comprising means for normally supplying said current of distinctive character to the rails of each of the sections in each of the stretches and to which current of distinctive character the track relays are non-responsive, means for each stretch governed by the systems of circuits associated therewith for cutting oh the supply of said current of distinctive character from the rails of all of the sections in the stretch which are in advance of a train which has entered the stretch from either end during movement of such train through the stretch, and means for each single track stretch governed by the systems of circuits associated therewith for rec-stablishing the supply of said current of distinctive character to the rails of the sections in the stretch behind a train therein as soon as such sections are vacated.

6. A supplemental signaling system for a stretch of railway track through which special vehicles as well as trains are operated at times, in two directions, said special vehicles being equipped with insulated wheels and having indication means responsive to current of a distinctive character in the track rails, the rails of said stretch being divided into track sections each of which is provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, said stretch being provided with railway signals for governing the movement of trains through said stretch, and with line circuits governed by the track relays of the track sections in said track stretch for controlling said signals, said supplemental signaling system comprising means for normally supplying current of said distinctive character to the track rails of each unoccupied track section in said stretch and to which current of distinctive character the track relays are non-responsive, and means governed by the track relays through the medium of the line circuits which control said signals for cutting off the supply of said current from the track rails of an intermediate section in said stretch when any one of the track sections in said stretch on either side of said intermediate section is occupied by a train.

7 A supplemental signaling system for a stretch of single track railroad through which special vehicles as well as trains are operated at times in either direction, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsive to current of a distinctive character in the track rails, the rails of said stretch being divided into track sections each of which is provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, said stretch being provided with a principal signaling system comprising a first and a second system of line circuits governed by said track relays and extending in opposite directions in said stretch for the control of railway signals for governing the movement of trains into and through the stretch, said supplemental signaling system comprising means for each track section governed by the track relay for such section for supplying current of said distinctive character to the rails of such track section only when such section is unoccupied by a train and to which current of distinctive character the track relays are non-responsive, together with means governed by said systems of circuits for cutting off the supply of said current when the track stretch in which the track section is located is occupied by a train approaching said section from either direction.

8. A supplemental signaling system for single track railroads having the usual stretches of single track between the ends of passing sidings through which special vehicles as well as trains are operated at times, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsive to alternating current in the track rails, the rails of said single track stretches and of the main track stretches adjoining the passing sidings being divided into track sections each of which is provided with a track circuit comprising a source of direct current connected across the rails at one end and a direct current track relay connected across the rails at the other end, each of said single track stretches being provided with a principal signaling system comprising a plurality of railway signals for governing the movement of trains into and through the stretch in opposite directions and a first and a second system of circuits governed by the track relays of the track sections in said track stretch for controlling said signals, said supplemental signaling system comprising means for each track section in each single track stretch and governed by said systems of circuits for supplying alternating cur rent to the rails of such track section, each such means being eilective to supply alternating current to the rails of the associated track section only when said section is unoccupied by a train and then only if the single track stretch in which the track section is located is not occupied by a train approaching said section, said supplemental signaling system also including means for each of the track sections in the main track stretch adjacent a passing siding for supplying alternating current to the rails 01 such section under the control of the systems of circuits associated with the adjoining single track stretch so as to supply alternating current to the rails of said main track section only when the adjoining single track stretch is unoccupied or is occupied by a train moving away from said section.

9. A supplemental signaling system for single track railroads having the usual stretches of single track between the ends of passing sidings through which special vehicles as well as trains are operated at times, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsive to alternating current of a first or of a second distinctive character in the track rails, the rails of said single track stretches and of the main track stretches adjoining the passing sidings being divided into track sections each of which is provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, and adapted to be shunted by trains but not by said special vehicles, each of said single track stretches being provided with railway signals for the control of train movements and with a first and a second system of circuits governed by the track relays of the track sections in said track stretch, for the control of said signals, said two systems of circuits controlling signals governing movement of traffic into and through the stretch in opposite directions, said supplemental signaling system comprising means for each track section in each single track stretch governed by the track relay for said section for supplying current of one distinctive character to the rails of the associated track section only when said section is unoccupied and then only if the single track stretch in which the track section is located is unoccupied or is occupied by a train moving away from said section, and means at each end of each passing siding for causing the current supplied to the rails of the adjoining track section in the adjoining single track stretch to at times have said first distinctive character and to at other times have said second distinctive character, depending upon traflic conditions in the main track stretch adjoining the associated passing siding.

10. A supplemental signaling system for single track railroads having the usual stretches of single track between the ends of passing sidings, through which special vehicles as well as trains are operated at times, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsive to current of a first or a second distinctive character in the track rails, the rails of said single track stretches and of the main track stretches adjoining the passing sidings being divided into track sections each of which is provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, each of said single track stretches being provided with railway signals for governing train movements controlled by a first and a second system of circuits governed by the track relays of the track sections in said track stretch, the two systems of circuits associated with each single track stretch controlling the signals governing movement of trains into and through the stretch in opposite directions, said supplemental signaling system comprising means for each track section in each single track stretch governed by rent of said first distinctive character to the rails of the associated track section only when said section is unoccupied and then only if the single track stretch in which the track section is located is unoccupied or is occupied by a train mov ing away from said section, and means at each end of each single track stretch for causing the current supplied to the rails of the track section at that end of the stretch to be of said second distinctive character when the system of circuits associated with the single track stretch on the remote side of the adjoining passing siding indicates that said remote single track stretch is occupied by a train approaching said siding and to be of said first distinctive character when said system of circuits indicates that said remote single track stretch is unoccupied or is occupied by a train moving away from said siding, and which train is beyond the first single track section of in the track rails, the rails of said single track stretches and of the main track stretches adjoining the passing sidings being divided into track sections each of which is provided with a track circuit comprising a source of current connected across the section rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, each of said single track stretches being provided with railway signals for governing train movements controlled by h a first and a second system of circuits governed by the track relays of the track sections in said track stretch, the two systems of circuits associated with each single track stretch controlling the signals governing movement of traffic into and through the stretch in opposite directions, said supplemental signaling system comprising means for each track section in each single track stretch governed by the track relay for said section and by the circuits for controlling said signals for supplying current of said first distinctive character to the rails of the associated track section only when said section is unoccupied and then only if the single track stretch in which the track section is located is unoccupied or is cocupied by a train moving away from said section, and means for each end of each single track stretch for causing the current supplied to the rails of the adjacent track section in said single track stretch to be of said first distinctive character according as the main track stretch adjoining the passing siding at that end of the single track stretch and the first section of the remote single track stretch adjacent the passing siding are unoccupied, and to be of said second distinctive character when a train in the remote single track stretch is approaching the passing siding.

12. A supplemental signaling system for single track railroads having the usual stretches of single track between the ends of adjacent passing sidings through which special vehicles as well as trains are operated at times, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsiveto current of a first or a second distinctive character in the track rails, the rails of said single track stretches and of the main track stretches adjoining the passing sidings being divided into track sections each of which is provided with a track circuit comprising a source of current con nected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, each of said single track stretches being provided with railway signals for governing the movement of trains controlled by a first and a second system of circuits governed by the track relays of the track sections in said track stretch, the two systems of circuits associated with each single track stretch controlling signals governing movement of traffic into and through the stretch in opposite directions, said supplemental signaling system comprising means for each track section in each single track stretch and governed by the track relay therefor and by the systems of circuits associated with the single track stretch in which the track section is located for supplying current of said first distinctive character to the rails of the associated track section only when said section is unoccupied and then only if the single track stretch in which the track section is located is unoccupied or is occupied by a train moving away from said section, and means at each end of each passing siding for causing said current supplied to the rails of the track section at that end of the siding and included in the stretch of main track adjoining the siding to have said second or said first distinctive character according as the systems of circuits associated with the single track stretch at the remote end of said passing siding indicate that said remote single track stretch is occupied by a train approaching said siding or indicates that said remote single track stretch is unoccupied or is occupied by a train leaving said siding, and which train is beyond the first single track section of said remote stretch adjacent the passing siding.

13. In combination with a section of railway track provided with a track relay which is normally energized by current supplied to the track rails and which releases due to the shunting effect of the wheels and axles when a train occupies said section, said relay controlling a railway signaling system for governing the movement of trains through said section, a supplementary signaling system for the protection of special vehicles in said section which are not adapted to shunt said track relay, comprising indication means on each special vehicle selectively responsive to current in the track rails of a character different from that normally supplied to said track relay and to which current of distinctive character the track relays are non-responsive, and means for supplying said current of different character to the rails of said section only when said section is not occupied by a train as manifested by the energized condition of said track relay.

14. In combination with a stretch of railway track divided into a plurality of sections each having a track relay which is normally energized by current supplied to the rails of its section and which releases due to the shunting effect of the wheels and axles when a train occupies its section, said stretch being provided with a railway signaling system controlled by said track relays for governing the movement of trains through said stretch, a supplementary signaling system for the protection of special vehicles in said stretch which are not adapted to shunt said track relays, comprising indication means on each special vehicle selectively responsive to current in the track rails of one character or another different from that normally supplied to said track relays, means associated with at least one of said sections and controlled by said track relays for supplying said current of one character to the rails of said one section as long as said stretch is unoccupied, said means being effective to cut off said current upon the approach of a train in one direction and to cause said current to have the other difierent character upon the approach of a train in the opposite direction.

15. A supplemental signaling system for a stretch of railway track through which special vehicles as well as trains are operated at times, said special vehicles being equipped with insulated wheels and having indication means thereon selectively responsive to current of a distinctive character in the track rails, the rails of said track stretch being divided into a plurality of successive track sections each provided with a track circuit comprising a source of current connected across the rails at one end and a track relay connected across the rails at the other end, adapted to be shunted by trains but not by said special vehicles, said track stretch being provided with a principal signaling system comprising a system of circuits governed by said track relays for the control of railway signals governing train movements into and through said stretch, said supplemental signaling system comprising means for supplying current of said distinctive character to the rails of each of the track sections in said stretch and to which current of distinctive character the track relays are non-responsive, and means associated with each section and governed by said system of circuits for cutting off said current of distinctive character from the rails of said section upon the approach of a train and also during the occupancy of said section by a train.

WILBUR V. GROSJEAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,566,331 Lewis Dec. 22, 1925 1,623,023 Wenholz Mar. 29, 1927 2,344,324 Pflasterer Mar. 14, 1944 2,390,010 Talbert Nov. 27, 1945 2,528,052 Grosjean Oct. 31, 1950 

